"Frank F. Burmo" <fburmo@online.no> writes:
> The following avg()-call gives me a result of: "2 days, 27:53:49.359573"...
> which must be wrong. There are only 24 hours in a day.
That's a false premise. Days and hours/minutes/seconds are independent
components of an interval. Some days have 23 or 25 hours, therefore
e.g. "48 hours" is not interchangeable with "2 days". If you want to
assume it is, see justify_hours().
regards, tom lane